Description/Features: 1.Note: The standard parts set you purchased is a combination of standard parts, the standard parts package for the smallest retail unit.2. If you have any extra standard parts after assembling the model, you can use them for secondary creation, please be aware of that.3. Please use the specified voltage USB power supply to power the device, and make sure the conveyor belt is pre-bent. Please check the running status of the motor after power on to prevent the motor from blocking.4. It is recommended to use this product indoors at room temperature. This product contains small parts, so please take precautions to prevent children (14 years old and under) from inhaling or swallowing.5.Whether you're a seasoned maker or just starting out, this model kit promises to provide hours of creative fun and learning.Specifications:Voltage: DC-5VMaterial: PlasticColor: As shownDue to different batches, there may be differences in product appearance, color, and printed text, which will not affect the use.Package Contents:20 x Marbles (Color random, No designation is accepted)2 x MotorOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.